A wiper device is generally comprised of a wiper blade, a wiper arm and a driving motor. The wiper blade includes a wiper rubber which wipes a surface to be wiped, such as an automobile windshield. The wiper blade is connected with the wiper arm which is associated with a driving motor, for example, through a linking member. The driving motor drives the wiper blade through the wiper arm so that the wiper rubber wipes the surface.
FIG. 12(C) shows a wiper arm 10′ used in a wiper device. The wiper arm 10′ includes a U-shaped tip portion (U-hook portion 12) which is designed to be connected with the wiper blade via a connector (hook-type securing).
FIGS. 12 (A) and (B) show a wiper arm 10 of a different type of securing. The wiper arm 10 includes a side pin 11 adjacent to its tip portion. The side pin 11 fits into an opening formed in the side of the wiper blade and is secured to the wiper arm 10 by means of a connector (side-pin type securing).
A different type of a connector is a multi-clip which couples the wiper blade with either the side pin 11 of the wiper arm 10 or the U-hook portion 12 of the wiper arm 10′. FIGS. 13 and 14 show examples of multi-clips.
In FIG. 13, a connector 100, for example, made of resin, includes side plates 101 and 102, and a main body portion 103 disposed between the side plates 101 and 102. An opening 104 is formed through the side plate 101, the main body portion 103 and the side plate 102. The opening 104 receives a pivot pin 9 of a wiper blade 1 so that the connector 100 is attached to the wiper blade 1. Openings 101A and 101B are also formed through the corresponding side plates 101 and 102 for receiving the side-pin 11.
The connector 100 further includes a main body 103 which has a forward portion 105 having an arcuate cross section. The U-hook portion 12 of the wiper arm 10′ fits to the forward portion 105. The main body 103 is also provided at its rearward portion with an upper plate 106 and a lower plate 107 which are disposed substantially in parallel to each other. The lower plate 107 is resilient and is bendable downward.
The wiper blade 1 includes side portions 2B and 2C which include insertion openings 2D and 2E, respectively. To secure the side pin 11 of the wiper arm 10 to the connector 100, the side pin 11 is inserted into the opening 2D of the wiper blade 1. The side pin 11 passes through the opening 101A, the interval space between the upper and lower plates 106 and 107, and the opening 101A of the connector 100, so that a tip portion 11A of the side pin 11 reaches the insertion opening 2E of the wiper blade 1 to be disposed through the insertion opening 2E.
As shown in FIG. 13(c), the lower plate 107 is bended in a direction indicated by the arrow in the figure so that the interval space between the upper and lower plates 106 and 107 is enlarged to allow the tip portion 11A of the side pin 11 to pass through the interval space. As shown in FIG. 13(b), when the side pin 11 reaches the insertion opening 2E, a small-diameter portion 11B of the side pin 11 is positioned between the upper and lower plates 106 and 107. Thus, the lower plate 107 returns to the configuration in which the lower plate 107 is substantially parallel to the upper plate 106. As a result, the side pin 11 is held between the upper and lower plates 106 and 107.
FIG. 14 shows a connector 110. Similarly to the connector 100, the connector 110 includes side plates 111 and 112, and a main body 113. The connector 110 also includes an opening 114 for receiving the pivot pin 9 of the wiper blade 1 so that the connector 110 is rotatable about the pivot pin 9. The main body 113 includes a forward portion 113A which has an arcuate cross section to fit within the inside of the U-hook portion 12.
The connector 110 also includes a receiving portion 115 for receiving the side pin 11. To secure the side pin 11 to the connector 110, the side pin 11 is inserted into the wiper blade 1 and the side plates 111, 112. The connector 110 is the rotated in a direction shown by the arrow in FIG. 14(C). Thus, the small-diameter portion 11A of the side pin 11 is fit into the receiving portion 115 so that the connector 110 secures the side pin 11 to the wiper blade.
The foregoing conventional connectors have the following drawbacks. In the connector 100 of FIG. 13, the side plates 106 and 107 hold the small-diameter portion 11A of the side pin 11. Thus, the contact area between the connector 100 and the side pin 11 is not sufficiently large. Also, the side plates 106 and 107 are apt to spread from the configuration for holding the side pin 11, since the plates 106 and 107 are made of resin. Thus, the connector 100 cannot sufficiently prevent detaching of the side pin 11 from the wiper blade.
Also, the side pin 11 is connected to the underside of the rearward portion of the connector 100. Thus, an operator cannot check the connecting by sight. Also, such an operation is hard work to carry out by hand since the space under the connector 100 is not enough large to put the fingers of the operator into there.
In addition, the side pin 11 is attached to a position which is offset rearwardly from the center of the wiper blade 1 (near the pivot pin 9). Thus, when the wiper blade is connected to the wiper arm 10, the total length of the wiper blade and the wiper arm 10 becomes too long so that the wiper blade may contact to an automobile body.
In the connector 110 of FIG. 14, the contact area between the connector 110 and the wiper blade 1 is too small since the receiving portion 115 of the connector 110 is formed in the side plates 111 and 112. Thus, the connector 110 cannot sufficiently provide the suppression of vibrations between the wiper blade 1 and the wiper arm 10, and the abrasion resistance of the wiper blade 1 and the wiper arm 10.
Further, the side pin 11 is received within the receiving portion 115 which is formed by undercutting. Thus, if the receiving portion 115 is wear out by abrasion, the side pin 11 may be detached from the receiving portion 115.